In the local lake the PS spawn about the same time as BG, but they do not nest in colonies, each PS has a nest sway from other fish by itself. The PS nests are 2x-3x as big as a BG nest too.
Thanks! That explains why I saw about a 5 inch SF guarding a huge 2 foot diameter nest last year. Visibility was not good enough to identify the SF. Sounds like it was probably a PS. Late summer I caught lots of fingerling SF in my minnow traps about 1 inch long that looked pretty much like BG fingerlings except they lacked the distinct vertical stripes I'm used to seeing on tiny BG. Probably PS fingerlings.